The theory of the country-of -origin image is discussed and the natural relations between county-of-origin image and the regional brand are explored. The paper points out that the dispersion of agriculture has intensified the natural relations to a large extent. The paper probes into the branding status of agriculture in Guanzhong-Tianshui economic zone and points out the problems of it. In the first place, the agricultural industrial system is complete but there is no unified agricultural regional brand; in the second place, the weak awareness on protecting brand leads to the irrational behaviors on damaging brand. From the perspective of the image of the country of origin, the branding mode of agriculture is established and the countermeasures on improving the competitiveness of agricultural products are put forward. Firstly, the leading role of the government should be fully displayed; secondly, the image protection of original production place and regional brand promotion of the agricultural region should be intensified; thirdly, the functions of local pillar industries in protecting image and regional branding should be fully made use of.